Film formation and foamability of cellulose derivatives: Influence of co-binders and substrate properties on coating holdout

Foams were prepared from hydrophobically modified ethyl(hydroxyethyl) cellulose (EHEC), methyl nanocellulose, and native microfibrillated cellulose (MFC). Their film- and foam-forming abilities, stabilities, and suitabilities for foam coating on different substrates were investigated. The role of EHEC as a polymeric stabilizing agent was also studied. The EHEC-MFC foams showed greater stability and water-holding ability under pressurized dewatering than MFC foams prepared in the presence of a surfactant. A foam could be created with methyl nanocellulose without any foaming agent. Selected nanocellulose gels and foam formulations were used to coat various substrates. The surface was efficiently closed by gel and foam coatings prepared from the methyl nanocellulose and EHEC solutions, which was ascribed to good coating holdout. Coatings on papers with different levels of smoothness/density and hydrophobicity/ hydrophilicity confirmed that foam-substrate interactions affected the coat quality. The air permeance was reduced by 99% and 64% with a methyl nanocellulose coating and an EHEC-MFC coating, respectively. An EHEC-MFC coating created a hydrophobic surface on a hydrophilic substrate, and methyl nanocellulose improved the oil resistance even at a low coat weight.

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The role of MFC and hydrophobically modified ethyl(hydroxyethyl)cellulose in film formation and the barrier properties of methyl nanocellulose film

Nordic Pulp & Paper Research Journal ◽

10.1515/npprj-2020-0099 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Johanna Lyytikäinen ◽

Sami-Seppo Ovaska ◽

Isto Heiskanen ◽

Kaj Backfolk

Keyword(s):

Contact Angle ◽

High Performance ◽

Film Formation ◽

Barrier Properties ◽

Hydroxyethyl Cellulose ◽

Hydrophobically Modified ◽

Coated Materials ◽

Ethyl Hydroxyethyl Cellulose ◽

Nanocellulose Film

Abstract There is currently a great demand for sustainable and bio-derived coatings for fiber-based packaging materials, which are technically implementable with a high performance. The aim of this work was to investigate the grease resistance of coatings prepared from methyl nanocellulose when applied on paperboard. Co-additives selected from native microfibrillated cellulose (MFC) and hydrophobically modified ethyl(hydroxyethyl)cellulose (EHEC) were used in order to determine their impact on film formation and crack resistance for folds. Small and moderate coat weights were applied in order to determine the critical coat weight for the barrier properties. It was found that high grease resistance can be achieved with methyl nanocellulose and a combination of methyl nanocellulose and MFC coatings. Contact angle determinations for water on uncoated and coated materials showed that EHEC-MFC films have a very high contact angle which is due to both the surface chemistry and roughness. This indicates and confirms that EHEC may facilitate the wetting of oil and greases. Methyl nanocellulose mixed with hydrophobically modified EHEC significantly changed the barrier properties indicating a change in the film formation.

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Skin and bubble formation in films made of methyl nanocellulose, hydrophobically modified ethyl(hydroxyethyl)cellulose and microfibrillated cellulose

Cellulose ◽

10.1007/s10570-020-03557-0 ◽

2020 ◽

Author(s):

Johanna Lyytikäinen ◽

Maria Morits ◽

Monika Österberg ◽

Isto Heiskanen ◽

Kaj Backfolk

Keyword(s):

Methyl Cellulose ◽

Microfibrillated Cellulose ◽

Hydroxyethyl Cellulose ◽

Effect Of Temperature ◽

Cellulose Derivatives ◽

Air Bubbles ◽

Oxygen Transmission Rate ◽

Hydrophobically Modified ◽

Film Forming ◽

Ethyl Hydroxyethyl Cellulose

AbstractThe use of nanomaterials and polymers from renewable resources is important in the search for sustainable alternatives to plastic-based packaging materials and films. In this work, self-supporting thin films prepared from derivatized and non-derivatized nanocellulose and cellulose derivatives were studied. The effect of drying temperature on the film-forming behavior of compositions comprising hydrophobically modified ethyl(hydroxyethyl)cellulose (EHEC), native microfibrillated cellulose (MFC) and nanocellulose made from methyl cellulose was determined. The interaction between the components was assessed from viscosity measurements made at different temperatures, the result being linked to a thermal-dependent association during liquid evaporation, and the subsequent barrier and film-forming properties. The effect of temperature on suspensions was clearly different between the materials, confirming that there were differences in interaction and association between EHEC–MFC and methyl nanocellulose–MFC compositions. The amphiphilic EHEC affected both the suspension homogeneity and the film properties. Air bubbles were formed under certain conditions and composition particularly in MFC films, dependent on the drying procedure. The presence of air bubbles did not affect the oxygen transmission rate or the oil and grease resistance. An increasing amount of MFC improved the oxygen barrier properties of the films.

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Alginate polyelectrolyte complexes with cationic hydroxyethyl cellulose derivatives: Role of the block structure

Polymer Science Series A ◽

10.1134/s0965545x06020118 ◽

2006 ◽

Vol 48 (2) ◽

pp. 171-176 ◽

Cited By ~ 3

Author(s):

Yu. A. Shchipunov ◽

I. V. Postnova

Keyword(s):

Block Structure ◽

Hydroxyethyl Cellulose ◽

Cellulose Derivatives ◽

Polyelectrolyte Complexes

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Spent Brewer’s Yeast as a Source of Insoluble β-Glucans

International Journal of Molecular Sciences ◽

10.3390/ijms22020825 ◽

2021 ◽

Vol 22 (2) ◽

pp. 825

Author(s):

Ionut Avramia ◽

Sonia Amariei

Keyword(s):

Emulsion Stability ◽

Extraction Process ◽

Brewer’S Yeast ◽

Brewer's Yeast ◽

Brewing Process ◽

Food Applications ◽

Water Holding ◽

Potential Food ◽

Insight Into

In the brewing process, the consumption of resources and the amount of waste generated are high and due to a lot of organic compounds in waste-water, the capacity of natural regeneration of the environment is exceeded. Residual yeast, the second by-product of brewing is considered to have an important chemical composition. An approach with nutritional potential refers to the extraction of bioactive compounds from the yeast cell wall, such as β-glucans. Concerning the potential food applications with better textural characteristics, spent brewer’s yeast glucan has high emulsion stability and water-holding capacity fitting best as a fat replacer in different food matrices. Few studies demonstrate the importance and nutritional role of β-glucans from brewer’s yeast, and even less for spent brewer’s yeast, due to additional steps in the extraction process. This review focuses on describing the process of obtaining insoluble β-glucans (particulate) from spent brewer’s yeast and provides an insight into how a by-product from brewing can be converted to potential food applications.

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Role of Biochar in Improving Sandy Soil Water Retention and Resilience to Drought

Water ◽

10.3390/w13040407 ◽

2021 ◽

Vol 13 (4) ◽

pp. 407

Author(s):

Ling Li ◽

Yong-Jiang Zhang ◽

Abigayl Novak ◽

Yingchao Yang ◽

Jinwu Wang

Keyword(s):

Climate Variability ◽

Sandy Soil ◽

Water Retention ◽

Sandy Soils ◽

Crop Productivity ◽

Future Research ◽

Soil Water Retention ◽

The World ◽

Water Holding

In recent years, plants in sandy soils have been impacted by increased climate variability due to weak water holding and temperature buffering capacities of the parent material. The projected impact spreads all over the world, including New England, USA. Many regions of the world may experience an increase in frequency and severity of drought, which can be attributed to an increased variability in precipitation and enhanced water loss due to warming. The overall benefits of biochar in environmental management have been extensively investigated. This review aims to discuss the water holding capacity of biochar from the points of view of fluid mechanics and propose several prioritized future research topics. To understand the impacts of biochar on sandy soils in-depth, sandy soil properties (surface area, pore size, water properties, and characteristics) and how biochar could improve the soil quality as well as plant growth, development, and yield are reviewed. Incorporating biochar into sandy soils could result in a net increase in the surface area, a stronger hydrophobicity at a lower temperature, and an increase in the micropores to maximize gap spaces. The capability of biochar in reducing fertilizer drainage through increasing water retention can improve crop productivity and reduce the nutrient leaching rate in agricultural practices. To advance research in biochar products and address the impacts of increasing climate variability, future research may focus on the role of biochar in enhancing soil water retention, plant water use efficiency, crop resistance to drought, and crop productivity.

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Improvement of Mechanical Properties of Noil Hemp Fiber Reinforced Polypropylene Composites by Resin Modification and Fiber Treatment

Advances in Materials Science and Engineering ◽

10.1155/2013/941617 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Zili Yan ◽

Jianchun Zhang ◽

Hua Zhang ◽

Hao Wang

Keyword(s):

Mechanical Properties ◽

Mechanical Analysis ◽

Interfacial Bonding ◽

Hydroxyethyl Cellulose ◽

Hemp Fiber ◽

Polypropylene Composites ◽

Hydrophobically Modified ◽

Fiber Treatment ◽

Fibre Treatment ◽

Adhesion Factor

The present study aims to improve the reinforcement of hemp fibre to polypropylene (PP) by simple resin modification and fibre treatment. Maleic anhydride grafted polypropylene (MAPP) was used as resin modifier by direct mixing with PP, and hydrophobically modified hydroxyethyl cellulose (HMHEC) was used as fibre treatment reagent by immersing fibre into its aqueous solution. The influences of fibre content, resin modification, and fibre treatment on the mechanical properties (tensile, flexural, and impact strengths) of composites were investigated. The change of interfacial bonding between fibre and resin in composites caused by MAPP and HMHEC was studied by scanning electron microscopy and dynamic mechanical analysis. Resin modification and fibre treatment were effective to enhance the mechanical properties of the composites. The improvement in interfacial bonding is quantitatively evaluated with adhesion factor.

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Enzymatic synthesis and phosphorolysis of 4(2)-thioxo- and 6(5)-azapyrimidine nucleosides by E. coli nucleoside phosphorylases

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.12.254 ◽

2016 ◽

Vol 12 ◽

pp. 2588-2601 ◽

Cited By ~ 3

Author(s):

Vladimir A Stepchenko ◽

Anatoly I Miroshnikov ◽

Frank Seela ◽

Igor A Mikhailopulo

Keyword(s):

Purine Nucleoside Phosphorylase ◽

Reaction Conditions ◽

E Coli ◽

No Formation ◽

Structural Peculiarities ◽

Substrate Properties ◽

Nucleoside Phosphorylases ◽

Derivatives Of

The trans-2-deoxyribosylation of 4-thiouracil (4SUra) and 2-thiouracil (2SUra), as well as 6-azauracil, 6-azathymine and 6-aza-2-thiothymine was studied using dG and E. coli purine nucleoside phosphorylase (PNP) for the in situ generation of 2-deoxy-α-D-ribofuranose-1-phosphate (dRib-1P) followed by its coupling with the bases catalyzed by either E. coli thymidine (TP) or uridine (UP) phosphorylases. 4SUra revealed satisfactory substrate activity for UP and, unexpectedly, complete inertness for TP; no formation of 2’-deoxy-2-thiouridine (2SUd) was observed under analogous reaction conditions in the presence of UP and TP. On the contrary, 2SU, 2SUd, 4STd and 2STd are good substrates for both UP and TP; moreover, 2SU, 4STd and 2’-deoxy-5-azacytidine (Decitabine) are substrates for PNP and the phosphorolysis of the latter is reversible. Condensation of 2SUra and 5-azacytosine with dRib-1P (Ba salt) catalyzed by the accordant UP and PNP in Tris∙HCl buffer gave 2SUd and 2’-deoxy-5-azacytidine in 27% and 15% yields, respectively. 6-Azauracil and 6-azathymine showed good substrate properties for both TP and UP, whereas only TP recognizes 2-thio-6-azathymine as a substrate. 5-Phenyl and 5-tert-butyl derivatives of 6-azauracil and its 2-thioxo derivative were tested as substrates for UP and TP, and only 5-phenyl- and 5-tert-butyl-6-azauracils displayed very low substrate activity. The role of structural peculiarities and electronic properties in the substrate recognition by E. coli nucleoside phosphorylases is discussed.

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